Customer Reviews

IRWIN Cobalt High Speed Steel Drill Bit, 7/32 is rated
3.3 out of
5 by
3.

Rated 4 out of
5 by
Cool hand from
Cobalt BitsI' m a tradesmen working for my self so I need quality & durability. Irwin has both at a reasonable price. Cobalt bits are designed for harder metals like stainless steel so they are more brittle then other bits and do not tolerate any flexing .If you wabble them to widen a hole they will snap. You must use exact perpendicular force to the work surface or they will snap. So slow down the rpm but increase the pressure. Cool the bit down with water or use cutting oil they will last many times over.

Date published: 2017-05-27

Rated 1 out of
5 by
Skins from
cobalt drill bitsBought a new set of bits yesterday and I needed to drill6 holes through both 1/8" & 1/4" Angle iron bed frame material. The cobalt bits I bought failed miserably, could hardly get it done. Ended up having to step drill to get 6 - 1/4" holes through the material. I won't buy Irwin bits again!!

Date published: 2015-04-01

Rated 5 out of
5 by
Randy Brumback from
Mr.These cobalt drill bits are the only thing that will drill into hardened bolts and metals. I have tried standard bits on hardened metal before not knowing what grade the metal was. The standard bit dulls almost immediately so I reach for the cobalt bits. They will sink on through the metal with no problem. The only cons are they are more expensive and they will break easily if you put force perpendicular to the bit instead of linear.